Catalyst Pharmaceuticals Inc (NASDAQ:CPRX), a biopharmaceutical company focused on developing and commercializing innovative therapies for people with rare debilitating diseases, today announced that the Company has received a “Refusal to File” letter from the US Food and Drug Administration (FDA) regarding its New Drug Application (NDA) for Firdapse® (amifampridine phosphate). Firdapse is Catalyst’s investigational drug candidate for the symptomatic treatment of Lambert Eaton myasthenic syndrome (LEMS) and congenital myasthenic syndromes (CMS).

The “Refusal to File” letter states that after a preliminary review, the FDA has found that the application, which was submitted in December 2015, was not sufficiently complete, and requests additional supporting information.  The letter does not provide comment on the acceptability of the submitted clinical data, and no judgment is made in the letter on the efficacy or safety of Firdapse.  Catalyst plans to request a meeting with the FDA as soon as possible to discuss the FDA’s comments on Catalyst’s NDA submission and to hopefully reach an understanding as to what will be required for the Firdapse NDA to be filed by FDA for review.

“We expect to work closely with the FDA over the coming weeks in an effort to resolve the open issues and to define a path forward for a successful resubmission of our application at the earliest point in time,” said Patrick J. McEnany, Chairman and CEO of Catalyst. “We remain focused on delivering on our promise to transform the way people living with LEMS and CMS are provided access to a safe and effective, FDA approved therapy. Additionally, our Expanded Access Program continues to enroll new patients and provide Firdapse at no cost to patients who meet the enrollment criteria.”

Catalyst has previously received Orphan Drug Designation for Firdapse to treat LEMS and CMS, and Breakthrough Therapy Designation for Firdapse to treat LEMS. (Original Source)

Shares of Catalyst Pharmaceutical are tumbling nearly 19% in pre-market trading. CPRX has a 1-year high of $5.80 and a 1-year low of $1.57. The stock’s 50-day moving average is $2.01 and its 200-day moving average is $3.00.

On the ratings front, Roth Capital analyst Scott Henry reiterated a Buy rating on CPRX, with a price target of $7, in a report issued on December 15. The current price target implies an upside of 278.4% from current levels. According to, Henry has a total average return of -1.3%, a 31.0% success rate, and is ranked #2571 out of 3610 analysts.

Catalyst Pharmaceuticals Inc is a biopharmaceutical company. The Company is engaged in the development and commercialization of prescription drugs targeting rare (orphan) neurological diseases and disorders.